{ "id": "1806.07502", "version": "v1", "published": "2018-06-19T23:33:45.000Z", "updated": "2018-06-19T23:33:45.000Z", "title": "Time-dependent polynomials with one double root, and related new solvable systems of nonlinear evolution equations", "authors": [ "Oksana Bihun", "Francesco Calogero" ], "categories": [ "math-ph", "math.MP" ], "abstract": "Recently new solvable systems of nonlinear evolution equations -- including ODEs, PDEs and systems with discrete time -- have been introduced. These findings are based on certain convenient formulas expressing the $k$-th time-derivative of a root of a time-dependent monic polynomial in terms of the $k$-th time-derivative of the coefficients of the same polynomial and of the roots of the same polynomial as well as their time-derivatives of order less than $k$. These findings were restricted to the case of generic polynomials without any multiple root. In this paper some of these findings -- those for $k=1$ and $k=2$ -- are extended to polynomials featuring one double root; and a few representative examples are reported of new solvable systems of nonlinear evolution equations.", "revisions": [ { "version": "v1", "updated": "2018-06-19T23:33:45.000Z" } ], "analyses": { "subjects": [ "70F10", "70K42" ], "keywords": [ "nonlinear evolution equations", "solvable systems", "double root", "time-dependent polynomials", "time-dependent monic polynomial" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }